1. Field of the Invention
This invention relates to reactor mixers and more specifically to mixers having means for transferring heat to or from the materials being mixed.
2. Description of the Prior Art
Many reactions in the chemical industry are carried out in pressure tight vessels called reactors which usually have a motor driven stirrer and means for transferring heat to or from the ingredients according to the temperature requirements of the reaction. The heat transfer means normally consists of a pipe coil inside the reactor or a double-walled jacketed portion surrounding the reactor vessel for circulating heating or cooling fluids such as steam or refrigerated brine.
These conventional reactors are relatively inefficient both in their mixing effectiveness and their ability to control the reaction temperature, particularly in the cases of highly endothermic or exothermic reactions or reactions in which the optimum temperature differs substantially from the ambient temperature. In such cases, the heating and cooling systems are not adequate to transfer heat to or from all portions of the materials being mixed at rates sufficient to maintain a relatively uniform temperature throughout the mixture.
As a result, the times to complete such reactions in conventional reactors are much longer than would be obtainable under more uniform conditions, and the yields may be reduced because the reaction in localized regions of the reactor may occur at other than optimum temperature and between insufficiently mixed reactants.
High energy centrifugal pump blenders are commerically available, but they are primarily adapted for blending dry ingredients or gases into liquids in processes that do not usually involve chemical reaction and the transfer of heat to or from the mixture. An example of such blenders is the equipment sold by the Tri-Clover Division of Ladish Co. under the trademark TRI-BLENDER.